<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>2.2 试用栅格系统完成响应式布局</title>
    <style>
        * {
            box-sizing: border-box;
            padding: 0;
            margin: 0;
        }

        img {
            width: 100%;
        }

        body {
            padding-top: 100px;
        }

        .container {
            background-color: #eee;
        }
    </style>
    <link rel="stylesheet" href="css/grid.css">
</head>
<body>
    <div class="container">
        <!-- <div class="row">
            <div class="col-md-4">
                <img src="img/2-1.jpg" alt="cellphone">
            </div>
            <div class="col-md-4">
                <img src="img/2-2.jpg" alt="cellphone">
            </div>
            <div class="col-md-4">
                <img src="img/2-3.jpg" alt="cellphone">
            </div>
        </div> -->

        <!-- <div class="row">
            <div class="col-md-5">
                <img src="img/2-1.jpg" alt="cellphone">
            </div>
            <div class="col-md-5">
                <img src="img/2-2.jpg" alt="cellphone">
            </div>
            <div class="col-md-5">
                <img src="img/2-3.jpg" alt="cellphone">
            </div>
        </div> -->

        <!-- <div class="row">
            <div class="col-md-4">
                <img src="img/2-1.jpg" alt="cellphone">
            </div>
            <div class="col-md-4">
                <img src="img/2-2.jpg" alt="cellphone">
            </div>
        </div> -->

        <!-- <div class="row">
            <div class="col-md-4">
                <img src="img/2-1.jpg" alt="cellphone">
            </div>
            <div class="col-md-4 col-md-offset-4">
                <img src="img/2-2.jpg" alt="cellphone">
            </div>
        </div> -->

        <!-- <div class="row">
            <div class="col-md-4 col-md-push-4">
                <img src="img/2-1.jpg" alt="cellphone">
            </div>
            <div class="col-md-4 col-md-pull-4">
                <img src="img/2-2.jpg" alt="cellphone">
            </div>
        </div> -->

        <!-- <div class="row">
            <div class="col-md-4">
                <img src="img/2-1.jpg" alt="cellphone">
            </div>
            <div class="col-md-4">
                <img src="img/2-2.jpg" alt="cellphone">
            </div>
            <div class="col-md-4 d-none d-md-block">
                <img src="img/2-3.jpg" alt="cellphone">
            </div>
        </div> -->

        <div class="row">
            <div class="col-md-4">
                <img src="img/2-1.jpg" alt="cellphone">
            </div>
            <div class="col-md-4">
                <img src="img/2-2.jpg" alt="cellphone">
            </div>
            <div class="col-md-4 d-md-none">
                <img src="img/2-3.jpg" alt="cellphone">
            </div>
        </div>

    </div>
</body>
</html>